Need Help ! LED Proco Rat RI mod

[Mike Vilogi]

Hello,
I am trying to get some help modding my Vintage Rat Re-issue. I have a 3pdt , 10k , and an LED but am having a heck of a time trying to figure out how to wire it to get the LED set up properly.

I have wired pedals with True Bypass and LED before, but the main problem is I can`t seem to figure out what connections running from switch are the GROUND, V+, OUTPUT, INPUT, etc ( which connections coming from the switch are which)



I know that this topic has been covered for other model Rat boards, but I have looked all over and haven`t found an edition for the 90s RI.



Any help breaking down the proper wiring would be a huge help.


I am using this chart as reference, but Cant seem to figure out what corresponding wires are the ones running off the Rat Switch.

[Kipper4]

Email sent buddy welcome to the forum.
id post a picture reply but my image shack is playing up

[Kipper4]

according to this schematic there is no buffering on bypass. If its the correct one for your model.
i just googled up proco rat re issue


http://www.diystompboxes.com/pedals/PCRAT1.GIF

[GGBB]

That schematic is not the right one - it most likely is the original "bud box" prototype RAT.  Here's an accurate one covering all production  RAT variations:  http://www.aronnelson.com/gallery/main.php/v/diyuser/GGBB/Multi-RAT.png.html

If you want to, you can mount your LED and its resistor directly on the PCB and use other unused pads to do this (others should note that these directions aren't for all RATs - just ones with the "Multi-RAT" PCB like yours).  This will keep things neat and tidy and limit the number of wires hanging around to 2.  If you don't want the LED mounted on the PCB, you can still use this wiring but just connect the LED to its pads via wires.  

Obviously the LED goes in the hole.  In your picture, the two PCB pad holes below the LED hole are for the LED - the left one is the anode (positive).  The resistor position beside it marked R14 is for the LED resistor - insert whatever resistor value is appropriate for your LED. To the left of the switch are two diode positions marked D4 and D5 and a transistor position marked Q2.  Jumper the right hole of Q2 to the top hole of D5 (the two holes closest to each other) - this is DC power.  D4 now becomes where you need to connect the 2 wires that will go to the LED switch.

For the switch replacement, the easiest thing to do is to rotate the 3PDT 90 degrees from how it is in that diagram so that one side is on and the other is off, as opposed to top and bottom on/off.  Then, ignoring the middle row, connect the new switch exactly the same as the old one.  Use the left half of the middle row to toggle your LED.

[Mike Vilogi]

Ok. I got it to so Q2 and D5 are jumped and the Led resistor is in place.

What two cable go into D4?

Is D4 the slot now for both the Ground and V+?

[GGBB]

Yes - turn the new 3PDT switch sideways as I described (sideways when compared to the diagram you posted).  It doesn't matter which way you turn it, just make sure that when you are looking at the back of the switch just like in the picture, the connections are between center and left/right, not center and top/bottom (left side is the on position and the right side is off). 

You want this way:



NOT this way:




Wire the top and bottom rows exactly the same as the current switch.  Connect one wire from each pad of D4 to the left and center switch lugs in the middle row.  It doesn't matter which goes to which.

[Mike Vilogi]

Got the led working, one of the pads lifted on the board when I was removing the original switch. I noticed that there was another pad in line with the one that lifted ( an open one that was not previously in use, probably for another model of rat) and made use of that.
The top middle terminal is the one I scooched to the side alittle

Tested out pedal after some trouble shooting.
At first would not pass effect signal.

Now it works great. I cut the jumper that is shown in the one diagram and everything worked like a charm ( on the 3pdt)

Is it necessary, and if so, where is it supposed to go with the 3pdt is rotated to the left?

ANywho, works like a charm now, and I have a nifty purple Led. Switch is silent, and a big improvement over the stock switch.

Thanks to all that helped , it was very very much appreciated!

[Kipper4]

Good work.

[GGBB]

Got the led working, one of the pads lifted on the board when I was removing the original switch. I noticed that there was another pad in line with the one that lifted ( an open one that was not previously in use, probably for another model of rat) and made use of that.
The top middle terminal is the one I scooched to the side alittle

The important thing is that it works properly, but normally the "spare" holes around the switch are for different wiring for different RATs and shouldn't be used otherwise.  If you used the spare hole directly beside the top center switch hole, that is bad and should not work - it is DC power whereas the switch is the PCB input.  If you used the spare hole beside the right top switch lug (from the back of the switch) then that is the same connection so will work fine.

There are no jumpers necessary since you are not using the scheme in that diagram.  The PCB takes care of the jumpering.

Here's a giant pic of the back of this PCB from my Vintage Reissue RAT for reference:

http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=45179

And here's the front:

http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=45176